Syntax Magazine

SYNTAX

Serving Timex-Sinclair
Personal Computers

VOL. 4 NO. 9

A PUBLICATION OF THE HARVARD GROUP

ISSN 0273-2696

SEPT., 1983

IN THIS ISSUE

MEMOTECHf PRINTER INCOMPATIBILITY SOLVED

8K Programs

Distance . 14

Rhythm Fun . 16

Zip-to-State ,

State-to-Zip . 8

Better Scrolling . 6

Book Review
ZX81/Timex

Programming in BASIC
& Machine Language. ...22

Classified Ads . 22

Dear Editor . 12

Clarification

Winky Board II . 3

Errors . 3

Hardware Project

Cheap Power . 18

Hardware Review
Memotext Word

Processor . 4

Hidden REMs . 17

MC INKEY$ Subroutine ... 19
New Products

and Services . 2

News . 1

Program Access

Security System . 10

Program Improvement
SAVEing unSAVEable

Programs . 7

Software Review

ZXDIS Disassembler . 7

User Friendly
Legal Advice — Pt. II... 4

Users' Groups . 3

Vendor Reports . 3

Index of Advertisers

Byte-Back . 21

E-Z Key . 10

Suntronics . 5

SYNTAX . .

Memotech reports the cause of Memopak/TS2040
printer incompatibility — 3 unneeded printer
capacitors (C4-C6). We (Jun.83) reported the
cause as inadequate power supplies; this lat¬
er proved true for only some TS2040S. Con¬
tact Memotech to learn the needed modifica¬
tions. Memotech Corp., 7550 W. Yale Ave.,
Denver , CO 80227, 303/986-1526. (See New
Products' COMPUMENTOR for another fix.— LFV)

TS1500 RAM TROUBLE

Industry sources inform SYNTAX that testing
of several RAMs — Memotech, Byte-Back, Glad¬
stone, Persona, and D'ktronics — shows they
will not work with current TS1500 demos.
(Timex could still alter the retail models.)
The reason: RAM CS is disabled (Timex RAMs
do not modify RAM CS). TS1000 software, and
hardware in the 8K-16K block (such as paral¬
lel printer ports, and some Memotech prod¬
ucts) do work with demo 1500s. Timex plans
to distribute 25-30,000 units about 9/1.

TS2068 UPDATE

TS2068s may grace your mailboxes by the end
of September. Timex says Reagan's FCC cuts
delayed approval. You can order products by
direct mail from Timex— Timex Computer Corp.,
Waterbury, CT 06720, 203/573-5000. Telephone
first to confirm price & model availability.

NETWORK INTERFACE FOR SPECTRUM

Sinclair Research announces the ZX Interface
I, enabling 64-machine, 100 Kbaud local area
networking and modem transmission. Available
in about a month; priced about $140 (US) with
RS232 interface, software. Micro-X Ltd., 5
Coverdale Rd., Brondesbury, London NW21 4DB,
UK, 011-44-1-459-1089. SYNTAX believes Timex
will produce a similar device for the TS2068.

1

NEW PRODUCTS AND SERVICES

Surge clamping diodes, 0.21"x0.38"
max. dimensions, 1" lead, 5V TTL,
$4.25. 11. IV, 15.3V $4.50 each.

P&H. Matthew Zenkar, 1432 Holcroft
Rd., Rochester, NY 14612.

SyncMaster offers 10% discount on
any TS software to users' groups
that have published newsletters for
at least six months. Send name,
address, contact name, two most
recent newsletters. SyncMaster,

POB 511, Oak Ridge, NC 27310.

Solutions to exercises in The Com¬
plete Sinclair ZX81 and Timex TS
1000 BASIC Course (Melbourne House)
for $5/listing. IK RAM. John B.
Carson, Jr., 11200 Lockwood Dr.,
#307, Silver Spring, MD 20901.

The Computer NEWSletter indexes
SYNTAX articles and other TS publi¬
cations (TI, TS, Atari edition).

10 issues/yr ,/$15. The Directory
of Computer Books in Print lists
publications. 5 updates/yr/$10.

The Computer NEWSletter . POB 952,
Cleveland, OH 44120, 216/283-8871.

SUNRISE/SUNSET program calculates
sunrise and sunset times. CALENDAR
PLANNER stores year's personal
events. Each tape 16K, $9.95 (CA
res. add tax.) I.M.S. Enterprises,
POB 4503, Lancaster, CA 93539.

SCREEN-FILE index holds over 17,000
characters in only 16K, $19.95.

Banta Software, 8088 Highwood Way,
Orangevale, CA 95662, 916/722-4895.

User's group members — 10% off total
purchase price until 9/25/83. 16-

64K DATA MASTER $5.95, 16K EXTEND¬
ER-6 TOOLKIT $4.95, 2K or greater
(Hunter NVM) NVM TOOLKIT $4.95. L.
Harmon, 4909 Clearlake Dr.,
Metairie, LA 70002.

JOGMATH teaches basic math skills.
$12.75 tape+$1.25 P&H. ZX-PANDING,
POB 25, Newton, NC 28658.

Microtrends Computer Festival and
Expo for the Future, TS section.

Ft. Mason Center, San Francisco,
admission $7.50. Micro Byte Pro¬
ductions, 1127 Pope St., St.

Helena, CA 94574, 707/963-2983.

SCOVI (Software controlled Video
Inverter) inverts video display,
merges with program. 16K, $9.95.
MXP Series solves complex expres¬
sions in math, physics, eng.,

$20.95 ea., Nucleus module $15.95,
ea. 16K. SYBER INC., POB 972,

Ocean Spring, MI 39564.

TS-ART graphics — sets any bkgrnd.,
defines new graphic commands,

$12.95 + $1.50 S&H. KSOFT CO., 845
Wellner Rd., Naperville, IL 60540.

E-Z Key joystick plugs into E-Z Key
60 keyboard, functions like arrow
keys. $29.95, E-Z Key, Suite 75,
711 Southern Artery, Quincy, MA
02169, 617/773-1187.

PI2040 printer interface allows
peripheral compatibility with
TS2040. Works with all Memotech
products. Sold with PC2040 ribbon
cable, has expansion connector for
additional piggy-back add-ons.
$37.95 + $2.50 P&H. COMPUMENTOR,
Suite 405, 1919 14th St., Boulder,
CO 80302. MC/VISA orders 800/458-
5858 x577 , in CO 800/458-4545 x577.

ZX Spectrum discounts: 16K $122.43
(79.50 pounds), 48K $156.31 (101.50
pounds). Micro-X Ltd., 5 Coverdale
Rd., Brondesbury, London NW2 4DB,
UK, 01-459-1089.

Glare-Guard designed for use with
ZX/TS computers, fits 12" screen.
Amber, reduces glare. $6.95+$l
P&H. R. Dyl , 15 Kilburn Ct., New¬
port, RI 02840, 401/849-3805.

Suburban Computer Fair, TS section,
Norwood, MA, Sept. 24-25, $4.50.
Contact Linda Barbrick, Technology
Mktng. Co., POB 122, Quincy, MA
02170, 617/773-5197.

2

SYNTAX ERRORS

VENDOR REPORTS AND NOTES

Russell Crum reports an error in
lines 750 and 800 in RETURN ON
INVESTMENT (Aug. 83 p.8) Change
both from GOTO 830 to GOTO 820 to
prevent endless looping for data
combinations that cause iterative
computations to fall below 0.1%.

Add MicroSync's phone number to
VENDOR REPORTS (Jun.83). Micro-
Sync, 162R Marlboro St., Keene, NH,
603/352-8575. Tech, help T, Th 3-6
PM, nontech, problems M-F 3-6 PM.

CLARIFICATION

Winky Board manufacturer Gerry Rus¬
sell sent the following clarifica¬
tions and additions to the Winky
Board II review (Aug. 83): The SAVE
filter feature should be used only
if high frequency RAM pack noise
prevents SAVEing. LEDs indicate
output, not recording levels. Use
of tape head alignment as suggested
in the manual improves LOADing.

Kit assembly requires more than
three solder joints. Burned out
LEDs will be replaced free. Winky
is not advertised as a tape sound
conditioner or tape filter. Winky
comes with a money-back guarantee
if not happy. Gerry adds to USER
FRIENDLY LEGAL ADVICE (Aug. 83): It

is legal to copy a purchased copy¬
righted tape for your personal use.

ZX/TS USERS1 GROUPS

Hollywood, CA: Timex Users Co-op,
Charles Miller, 1223 N. Hoover St.,
Los Angeles, CA 90029.

Ypsilanti, MI: Clive Norman, 554
Rosedale Rd., Ypsilanti, MI 48197.

Dallas, TX: New contact person:
Julie Barrett, 2624 E. Park Blvd.,
Plano, TX 75024, 214/578-8255.

Hagerstown, MD: Jr. group, up to
age 16, Toby Posch, 908 View St.,
Hagerstown, MD 21740.

Brainchild's Gwen Marsh happily
reports that all Kolorworks back
orders are filled, and future de¬
liveries should take about 4-6 wks.
Kolorworks $149.95, $4.95 S&H, demo
tape $9.95. Brainchild, POB 506
Pewaukee, WI 53072, 414/691-3903.

Proprietary International's Randy
Wear says delivery of ZT21000 co¬
processors will be delayed until
about Oct. 1. PI, 131 LaSalle Rd.,
Streamwood, IL 60103, 608/255-2325.

SYNTAX and other customers cannot
locate Frog Software or its prin¬
cipals by mail or phone. You can
request a complaint form to initi¬
ate action if Frog has your money
and you have nothing to show for
it. Robert Abrams, Atty. General,
Bureau of Consumer Fraud and Pro¬
tection, State Capital, Albany, NY
12224, 518/474-5481.

Don't expect your Kopak keyboard
until early October, and expect
indefinite delays on Z-99 Com¬
pilers, reports Kopak's Robert
Schiller. E-Z Loaders were being
shipped at press time. Kopak, 119
Peter St., Union City, NJ 07087.
800/222-0903, in NJ 201/864-4410.

Downsway Electronics, UK, now manu¬
factures TS RAM packs in Indio, CA.
Downsway also distributes TS soft¬
ware by mail order and deader s in
North America. Downsway Califor¬
nia, Inc., 81824/D6 Trader Place,
Indio, CA 92201, 619/342-1223.

Paul Hunter's nonvolatile memory
board costs more as of Sept. 1.
Basic 2K kit $32.95, additional
three 6116LP-3 $19.00, $1.95 S&H

per order. Contact Paul for com¬
plete price list. Paul tells us he
has sold over 1,000 kits in Japan,
Australia and Malaysia, as well as
throughout Europe and N. America.
Paul Hunter, 1630 Forest Hills Dr.,
Okemos, MI 48864, 517/349-5650.

3

USER FRIENDLY LEGAL ADVICE — PT. II

Should you sell or license
your program? Advantages to sel¬
ling your program: you get more
money more quickly, and avoid pos¬
sible low royalties if the program
sells poorly. If you sell, your
contract should specify warranties
and obligations post-sale (i.e.,
mods, debugging).

Licensing gives you more con¬
trol. A license allows you to
retain ownership and allows the
licensee to use or distribute your
program. You can license to com¬
panies in different parts of the
world. You can impose trade secre¬
cy limitations more easily in a
license vs. sale agreement. You
may get more income in royalties.

Run a credit check on any com¬
pany you sell or license to, by
requesting references or using a
credit check service.

Understand the contract com¬
pletely — US vs. world rights, the
length of term and if rights return
to you vs. company renewal option
after the licensing period expires.

Most license agreements in¬
clude royalties and an initial cash
payment (advance against royal¬
ties). The licensee can recoup the
advance out of your program's in¬
come before he pays your royalty.

If you're offered no advance,
you're not likely to make money.

NET MEANS NOTHING — an old law¬
yer's adage that's important to
remember. If your royalty is cal¬
culated against net income from
your program, the company can and
will deduct their expenses (adver¬
tising, shipping, etc.) from gross
income, calculating your royalty on
a very small amount. Definition of
income should be the company's en¬
tire proceeds from sales — the most
common and fairest agreement.

Jonathan Wallace, Esq., 51 E.
42nd St., Suite 1601, NY, NY 10017
(Wallace's clientele includes soft¬
ware designers. — LFV)

HARDWARE REVIEW

Product: Memotext Word Processor

From: Memotech Corp.

7550 W. Yale Ave .

Denver, CO 80227
Price: $49.95, $4.95 S&H

At last — a commercial word
processor for ZX/TS computers using
standard word processing functions!

Memotech supplies its word
processor on an EPROM. Its color
coordinates with your computer and
other Memotech add-ons. Mine sits
behind my Memotech keyboard and
parallel printer interfaces, and in
front of my 64K Memopak and Byte-
Back modem. Memotext supports both
the Memotech RS232 and Centronics
interfaces and works with many
printers. My full-size Seikosha
GP-250X printer produces nice copy
with Memotext.

Features: you can input at a

fast typing speed, two complemen¬
tary files are supported (text and
data files), you can set up prompts
within your text, and you can jus¬
tify your margins. You can word¬
wrap, move, search, exchange and
underline or boldface if your
printer supports these functions.

To use Memotext, turn it on
with its own on/off switch after
you see the K cursor. If you use a
64K RAM, first POKE in RAMTOP (POKE
16388,255, POKE 16389, 255, NEW) to
give you maximum memory.

Memotext does not work with
the Memotech HRG, despite an ade¬
quate power supply. Memotech
knows about this problem and is
working to solve it.

Overall, I am very pleased
with Memotext. One minor gripe —
Memotech should include actual
screen examples of text in the
manual, to facilitate use. But
after spending a short amount of
time with Memotext, everything
falls into place. Thanks again,
Memotech; keep up the good work.

Joseph Kernaghan, Hilton, NY

4

BEST KEYBOARD AVAILABLE!

For Your

ZX-81 /TS-1 000

□ Includes Shielded Case
□ Fully Warranted For 90 Days
□ Now In Stock

□ Hundreds of Satisfied Customers

NEW
LOWER
PRICE

EASY TO
INSTALL

• No Soldering

• No Modifications

SUN KD-81

If you’re tired of not knowing whether your data got entered or tired of pok¬
ing data in with one or two fingers, then it’s time to upgrade your ZX-81 to
a full size, professional keyboard. The SUN KD-81 KEYBOARD offers all
the ease and comfort of inputting your programs and text on a fast and ef¬
ficient professional-sized keyboard!

KD-81 FEATURES

• Full size keyboard with 41 keys

•Two color silk-screened key tops
for easy reading

• Key tops have commands and
graphics spelled out the same as
ZX-81

• Extra shift key for real keyboard-
style typing

• Full size space bar

• Allows touch typing

• Rear cutout allows any RAM or

expansion module to be plugged
in

• Keyboard comes with own cables

• Keyboard case holds both
keyboard and computer with room
to spare

• High impact plastic case with
vaporized metal shielding

• Easy assembly — no soldering,
no modifications

• Measures 10%" x 71/*" x 2%"

DEALER INQUIRIES WELCOME

GET A BETTER PICTURE WITH SAMWOO

SAMWOO provides a much better picture for your Sinclair
Computer than your TV monitor. Simple modification pro¬
cedure includes easy-to-follow instructions.

9" 18Mhz BANDWIDTH

Green . $115.00

Orange . 119.00

12" 12Mhz BANDWIDTH

Green . $124.00

Orange . 127.00

Add $7.50 Shipping and Handling for this item.

MONITORS

Features:

• Composite Video
Input/Output

• Switchable Input
Impedance 75 or
lOKohm

• 750 Line Resolution
at Center and 500
Lines at Corners

• Dimensions are
12.13" x 11.34" x
11.65" for the 12"
model and 8.66" x
8.54" x 9.05" for the
9" model

Simple installation
steps included
with
each
kit.

RAM MODULES

• Built-in output connector for piggyback

• Up for mounting on ZX-81 & KD-81

• High-impact plastic case with vaporized metal
shielding

• 6.6" wide, 3.2" high, 1.08" deep

16K $49.95 MX-16KP

64K $119.00 MX-64KP

J

SUNTRONICS CO., INC.

12621 Crenshaw Blvd., Hawthorne, CA 90250

STORE HOURS: MON.-FRI. 9:00 am to 6:30 pm
SATURDAY 10:00 am to 5:00 pm

CALIFORNIA OUTSIDE CALIFORNIA TOLL FREE

213-644-1149 1-800-421-5775

(for Tech Info and Calif, orders) (Order Desk Only)

Mail Order — Minimum Order $10. Send Money Order or Check to P.O. BOX 1957 —
HAWTHORNE, CA 90250. VISA or Mastercard (please include expiration date).
Add $4.00 postage and handling to order. CA residents add 6% sales tax.

✓ v

BETTER SCROLLING

SCROLL subroutines in the Sin¬
clair 8K ROM run disappointingly
slow with BASIC arcade-type graph¬
ics games, especially those using
full graphic backgrounds. Several
programming techniques can speed up
SCROLLing functions to an accept¬
able level.

Type in listing one and RUN
it. You'll see the inverse numbers
and letters PRINTed slowly across
the bottom of your screen.

Improve this by filling in the
bottom row with a 32-character
string (B$) as shown in listing
two. Even so, the characters still
visibly creep across the bottom,
because the 8K ROM SCROLL routine
collapses the last non-empty row
down to a single ENTER character
(118d) every time SCROLL executes.
When you PRINT this collapsed bot¬
tom row, ROM subroutines rebuild it
slowly, one character at a time.

30 l_et b $ =

Listing four demonstrates a
way that the bottom of the screen
can fill rapidly with a changing
pattern of characters. Lines 30-50
initialize variables B$, T, and A.
Line 70 calculates a displacement
(D) which varies with the sine of T
and ranges from 1 to 31. Line 80
fools row 21 into the filled state
(as above) , then slices B$ into two
smaller strings of length D-l and
32-D. This same line then PRINTS
these smaller strings in reverse
order for an amusing sine wave
graphics display. (For variety,
alter line 30 so that B$ contains
32 graphics characters of your
choice.) Experiment by using any
function to alter the displacement.

(I chose sine arbitrarily.)

30 LET =

Listing three demonstrates an
elegant solution to this problem
(first described by John Oliger,
SYNTAX, Apr. 82 p.6). Line 50
PRINTS AT 21,31; this effectively
rebuilds the collapsed bottom row
to its full state almost instantly,
rather than a character at a time.
This line continues by PRINTing AT
21,0;B$ to to properly place the
long string (B$) on the bottom row.
Now RUN listing three — you'll note
that it runs significantly faster;
the bottom row appears more quickly
than the eye can follow.

This sine wave display uses random
graphics characters in line 30,
listing four — LFV.

6

Listing five shows how to
nearly double the speed of listing
four. Lines 40-70 calculate all
displacements ahead of time and
store them in an array. When the
slicing, PRINTing and SCROLLing
execute in lines 100-130, the com¬
puter wastes no display time on the
calculation of the trig (or other
function). This technique, how¬
ever, eats up quite a bit of memory
in some applications.

These methods come in handy
for speeding up any BASIC software
that uses SCROLL. Try them in your
graphics game programs.

Dan Tandberg, M.D., Albuquerque, NM

PROGRAM IMPROVEMENT

SAVE CHR$ USR 832 "program
name" works very well to save my
unSAVEable programs (SYNTAX Jul.83
p.6). But the short time interval
between LOAD and SAVE (about five
seconds) prevents changing tapes to
SAVE the program, as the author
suggests. Instead, allow the sys¬
tem to go into SAVE and then press
BREAK (obtaining an error report).
Then LIST the program to find the
line with SAVE "program name." Set
your recorder in a normal, unpan-
icky time-frame. Next, enter GOTO
(line number with SAVE). This
method works well on all my unSAVE¬
able programs. Congratulations to
Gary for devising this trick.

Walter Kronk, Peabody, MA

SOFTWARE REVIEW

Program: ZXDIS Disassembler

Price: $14.95

ROM/RAM required: 8K/16K
Printed listings: No
Program listable: Yes
Language: MC , some BASIC

From: Scientific Software

6 W. 61 Terrace
Kansas City, MO 64113

Scientific Software's second
utility program seems as outstand¬
ing and useful as its first (ZXAD
Assembler and Debugger). ZXDIS
lets you to examine MC programs as
standard Z80 mnemonics and not a
sequence of numbers. You may dis¬
play mnemonics or hexadecimal data
and equivalent characters.

You can use ZXDIS easily. LOAD
the disassembler with name "ZXDIS".
After LOADing, it prompts you for a
relocation address. You can relo¬
cate it anywhere in memory: below
RAMTOP, between 2000H (8192) and
3FFF (16383), or remain at your
original LOADing location. After
relocation, run the utility by en¬
tering RAND USR #, where the # is
specified by the utility before it
moves. ZXDIS operates completely
from MC with no BASIC required af¬
ter relocation. RUN, then select
the desired function from the menu
by entering the correct character.

ZXDIS functions include MODE,
PRINT, ADDRESS, LIST, MEMORY MODI¬
FICATION, SEARCH, and TAPE/LOAD.

MODE switches the display be
tween disassembly and hex format.

PRINT (P) switches between
print and non-print modes.

ADDRESS displays a new address
when you type a four-digit hex num¬
ber. (Starting address is at loca¬
tion 0000H).

LIST function disassembles the
next 16 instructions (disassembly
mode) or 96 bytes (hex mode). Type
four hex digits (an address) and L
to display instructions or bytes
from the current address through
the address you entered.

7

Available from SYNTAX. . .

For computing beginners —

Crash Course in Microcomputers . $19.95

Covers hardware, machine language and
applications. Reviewed in SYNTAX , Oct. 1981.
Aad $1.50 shipping.

ZX80 Pocket Book $10.95

Includes ZX81 supplement. Covers Sinclair
BASIC, data and program listings.

Add $1.50 postage.

For advanced hardware/ software users —

Zilog’s Z80-Z80A CPU

Technical Manual . $7.88

Zilog’s Assembly Language

Programming . $15.75

Experiments in Artificial

Intelligence . $9.95

Add $1.50 postage.

SYNTAX back issues available, $4 each.

Call or write for our group subscription discounts.

SYNTAX • RD 2 Box 457 • Harvard, MA 01451
617 / 456-3661 cv.qoi

MEMORY MODIFICATION allows you
to modify the current byte by typ¬
ing a two digit hex number.

SEARCH allows you to search
for a byte of a particular value by
entering a two-digit hex value and

S. Your computer then searches
forward for the value, and displays
its address.

TAPE/LOAD function seems the
most useful. It allows LOADing and
LISTing of a program which self-
RUNS after LOADing. After entering

T, it prompts you to "start record¬
er and press ENTER." The machine
LOADS the first program it comes
to, ending with report code 9. You
can then LIST, disassemble or SAVE.

After using two other disas¬
semblers, ZXDIS wins my approval.
It's user-friendly, simple to use,
and gets the job done. I highly
recommend it if you're interested
in examining machine code or want
to backup nonLISTable programs.

Travis L. Miller, Lee's Summit, MO

ZIP— TO— STATE , STATE-TO-ZIP — 8K/16K

With lots of memory, many
computers can convert a zip into
the city and state. With a ZX/TS,
you can convert zip to state with a
short program.

Here's the technique we use at
SYNTAX to make sure our zip and
state match in our mailing list.

In sample zip code 48503, the digit
4 determines one of ten national
areas and the digits 85 determine
the state. All zip codes follow
this format. This program stores
state abbreviations, and correspon¬
ding zip ranges in the arrays S$
and Z$. S$ stores two-letter state
abbreviations and corresponding
places in Z$ contain lower and
upper ranges for the zip.

Note in the following chart
the state abbreviation for Michigan
(MI) in S$, between Indiana (IN)
and Iowa (IA) . Number 85 in 48503
lies between the corresponding num¬
bers in Z$ (80 and 99). The two-
letter zip code ranges are stored
as that number's character.

S$=" . . .11 |N | M |I |I | A | . . . "

Z $="... | 60 | 79 | 80 | 99 | 00 | 28 | ..."

For each national area, we
store the range in array C$. For
example, national area 0 is locat¬
ed in Z$ and S$ at positions 1-20.
The characters for 1 and 20 are
stored in C$ positions 1 and 2.

First, type in the following
program, typing 146 X's in line 1
and 20 X's in line 3. The X's hold
memory locations that will contain
data for zip-state conversions.

8

Now enter GOTO 10. At each
prompt, type in one number in the
following table (left to right,
consecutively). Line 30 POKES the
values for you.

Now change line 10 to read:

Type in GOTO 10 then ENTER. Type
in the following characters as you
did previously.

Now delete the previous lines
10-50 and add the following pro¬
gram, beginning at line 15. The
following lines 1-3 show what your
lines 1-3 should look like after
you POKEd in the previous tables.

To RUN the program, type in RUN and
choose a menu option (zip-state or
state-zip). Then enter either zip
or state to see the corresponding
match displayed. — RWK

NOT JUST A KEYBOARD REPLACEMENT
BUT AN ENHANCEMENT THAT GIVES
KEYBOARD FEATURES FOUND ONLY
ON MORE EXPENSIVE COMPUTERS

FOR FASTER & EASIER DATA ENTRY
WITH YOUR E-Z KEYBOARD . . .

Here at last, is a large 60 key TACTILE
FEEL keyboard that plugs into the same
connectors as the existing keyboard on
yourZX81. TIMEX/SINCLAIR 1000 or 1500

HERE THE CLICK ... FEEL THE SNAP!
for every key pressed (tactile feedback)

IT S THE ONLY KEYBOARD WITH ALL OF
THESE FEATURES:

• 60 moving keys solid (not rubber)

• Legends in three colors on the base (color coded by key functio

• Molded legends on keytops (no stickers)

• 8 automatic shift keys (no shifting required) for edit delete
single & double quotes colon semi-colon function and stop

• 2 shift keys

• Numeric keypad

above) is available for youi E-Z Key keyboard
Measurements Price

EC-11 (11 X 9 X 3 5 ') 24 95

EC- 14(14 X 9 X 3 5 ) 2995

JOYSTICK 29 95

$84.95

90 day warranty

S ORDER FORM

E-Z HEV

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EC 11 EC 14

$24 96 $29*95

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Mass residents add SS sales t a*

—

I Suite 75 STX
J 711 Southern Artery
I Quincy, Massachusetts 02169
V (617)773-1187

Artisans bring life to dreams and
shape futures by subtle choices of
design and execution. Our founding
editor, Ann L. Zevnik, led Syntax

to excellence, accuracy and utility
with her consummate skills. Ann's
influence will remain; Ann will
not. We will miss her wit, craft,
and knowledge. To those who follow
we commend this maxim: if I see
farther than others, it is because
I stand on the shoulders of giants.
Farewell ALZ; find a great dream.

PROGRAM ACCESS SECURITY SYSTEM

This short machine code pro¬
gram prevents program access with¬
out a code after you LOAD your
program. You set your own personal
security code. If someone tries to
enter the wrong code, the keyboard
locks up, forcing the user to power
down and reLOAD. When you enter
the right code, you can RUN, LIST,
and use the program as usual.

PROGRAM ACCESS works through a
small subroutine that scans the
keyboard after storing the machine
codes of each letter in the five-
letter password. If the five let¬
ters match the stored code, the
user gains access. If not, the
keyboard locks.

In the printed listing, lines
1-4 add the security mechanism and
self-SAVE routine. Lines 10-60
allow you to enter your code. Our
sample program begins at line 100.

We suggest typing in the pro¬
gram as listed, using the access
code SYNCE. Then, you can change
the code or program as desired.

(You will get a different Syntactic
Sum when you do this.) SAVE the
entire routine after you type it in
by hitting RUN then ENTER. When
you LOAD the program again, it
comes up RUNNING and asks for the
secret access code.

To enter the machine code in 1
REM, you can POKE in the following
values, beginning at address 16514.
Note that the bytes in addresses
16657-16662 do not appear in the
listed REM statement. (See HIDDEN
REMS for an explanation. — LFV)

Lawrence Coulter, Chelsea, MA

lO

PRQS00H ” ”

Mnemonics

INIT LD E , 05

PUSH DE

CALL PRINTLINE
"ENTER ACCESS CODE"FF

START

CALL KSCAN

INC L

JR NZ START

WAIT

CALL KSCAN

LD B,H

LD C,L

LD D,C

INC D

JR Z WAIT

CALL FNDCH

LD A, (HL)

CALL PRINT

STORE

POP DE

PUSH AF

DEC E

JR Z TEST

PUSH DE

JP START

TEST

LD B , 05

LD HL , CODE+4

TESTI

POP AF

CP (HL)

DEC HL

DJNZ TESTI

RET

FAIL

CALL CLR

CALL DLAYl

CALL PRINTLINE
"ACCESS IS DENIED
CALL DLAYl

JR FAIL

CLR

LD, DE , (DFILE)

INC DE

LD HL , 21

ADD HL ,DE

LD B , 20

LOOP

DEC HL

LD (HL) , 0

DJNZ LOOP

LD (DFCC) ,DE

RET . /

DLAYl

LD C ,FF

DLAY2

LD B ,FF

DJNZ -2

DEC C

JR NZ DLAY2

RET

CODE

"SYNCE"

PRINT

POP HL

LINE

LD A, (HL)

INC HL

PUSH HL

CP FF

RET Z

CALL PRINT

JR PRINTLINE

Some SYNTAX readers have ex¬
pressed concern that we may not
publish a problem that reflects
negatively on a SYNTAX advertiser.
In fact, we generally don't publish
problems without an answer. Our
policy: publish solutions to prob¬

lems, regardless of product. We
offer you more than a newsletter
catalog of problems. You own the
equipment — you know the problems
and need solutions. When we know,
you read it in SYNTAX.

Kirtland H. Olson, Publisher

DEAR EDITOR;

After one roll of paper, my ZX
printer appeared slightly ill; by
the end of roll two, cancer set in.
ZX could not LLIST even a five-line
program legibly. Terrible grinding
sounds emanated from inside. ZX
needed major surgery.

I timidly removed the four
long corner screws from the bottom,
then jiggled the top cover free,
and easily unclipped the revealed
single white wire. I removed the
top cover to see the motor, pulleys
and belt that move the little wire
styli. I noted with disgust that
black, irregular crud coated the
belt. I removed the belt, cleaned
it with a toothbrush, and placed it
back on the pulleys. (Use care
here not to damage the styli.)

It took several attempts to
reassemble the printer, since the
cable, feed switch and axles must
line up correctly with the top
cover. (Make sure to reconnect the
white wire.) My ZX printer now
runs beautifully.

Dan Tandberg, M.D., Albuquerque, NM

Here's a tip for those who
tackle expansion kits. I paid the
hard way to learn that the keyed
Timex plug-in modules can cause
serious damage when plugged into an
exposed board edge connector. I
ruined a 16K RAM by feeling for the

key-in-slot registration without
looking at the connection. When I
turned on the power, the screen
displayed strange activities and my
RAM pack had died. Of course, I
had an uncased kit module between
the computer and RAM pack. So for
those who build kits that may not
be cased right away, magic-glue a
small segment of plastic board per¬
pendicular to the end of the board
edge connector. Or, cement thin
plastic plates on the outside of
the 46-pin sockets. (Some of these
already fit closely in housed
units; Sinclair chose to cut down
50-pin connectors.)

If you computerize model rail¬
roads, please contact me.

Bruce Kott, 4360 Rolfe Rd.

San Diego, CA 92117

So. Bay Computer Club collect¬
ed these conversion formulas:

1 2

John Petersen, Manhattan Beach,

CA

I wired an Atari joystick to
my ZX81 following the procedure in
SYNTAX (Jun.82). The joystick
works fine, but I can't LLIST or
LPRINT. What's wrong?

Gary Hawkins, Weyerhauser, WI

Both of these functions are on one
diode line; perhaps the long wires
cause difficulty. Check for solder
bridges or other partial shorts on
your connections. It's not normal
for any connection we recommend to
disable the computer, BUT long
wires on the keyboard connector do
cause trouble, often with shifted
functions. Installing a connector
with short leads would be a simple
fix; just remove the joystick when
not using it. Replacing the cable
with one having lower capacitance
between wires would be a superior
repair. Use ribbon cable with
parallel conductors. Connect every
other wire to replace the six you
need, and leave the others discon¬
nected. — KO

Here's how I rebuilt my power
supply to avoid ZX81 crashes. My
original power supply had only a
1000 uF capacitor with 1 Amp maxi¬
mum output voltage regulator in¬
side. I rebuilt it with a Radio
Shack LM350T voltage regulator with
a maximum 3 Amp output. My two un¬
used 54,000 uF capacitors also went
in, between the full wave rectifier
and regulator. I also added a
20,000 uF capacitor between the
regulator and computer for addi¬
tional smoothing of DC voltage. A
timer delays the computer's start
by 12 seconds, allowing the capaci¬
tors 8 seconds to fully charge.

Ken Norton, Whitehall, MI

I have a more in-depth solu¬
tion than the one published in
response to a question from Paul
Crecca (SYNTAX, DearEd, May.83).
Here's how to modify VU-FILE to run
with QSAVE.

1. Hit BREAK to see BASIC listing.

2. Make the following changes:

1100 DIM F$ (9200)

3690 PRINT USR 32383
9995 FAST

Md 9996 PRINT USR 32383

3. POKE 19151,0

4 . CLEAR

5. SAVE the revised program, using
ZX81 SAVE command.

6 . LOAD QSAVE

7. LOAD the revised program, using
ZX81 LOAD command.

8. Put a fresh tape in the record¬
er, set to record, GOTO 9995.

VU-FILE now SAVES itself in QSAVE
format. It comes up RUNning on
reLOADing, ready for use. It still
asks for you to enter a name prior
to SAVEing files, even though QSAVE
does not use this feature. VU-FILE
stores the name and will label the
file with the Inform command.

W.D. Stevens, Tulsa, OK

When POKEing in machine code
to run my Zebra joystick, I hit the
Z key to exit, causing a repeat of
the last CODE I entered. Use this
program (with any addresses) to cut
down typing of repetitive codes.

10 FOR X=8192 TO 8220
20 INPUT Z
30 POKE X,Z
40 PRINT PEEK X
50 NEXT X

When you INPUT Z, you POKE the last
code entered into the X address.
Then you can hit Z to repeat codes.

Michael Bowman, Arab, AL

I developed a method of making
a tape with test tones to check my
recorder's head alignment. I re¬
corded my stereo test record (from
High Fidelity magazine) on my
stereo cassette recorder. I used
that tape to test my monaural (Sony
TR-215) recorder. The test tones
sound fine past 8000 cps, indicat¬
ing good azimuth.

Robert Jenkins, Chicago Heights, IL

13

f

DISTANCE — 8K/16K

DISTANCE computes the shortest
distance and true bearing from any
point on the earth's surface to any
other location.

Type in this easy-to-use pro¬
gram (line 10 has 97 spaces) and
input geographical coordinates when
prompted. Get latitude and longi¬
tude from a map or almanac. Enter
coordinates in degrees and tenths
(six minutes is 1/10 degree); enter
east longitude or south latitude as
a negative number, to distinguish
from west and north. For example,
enter 18 degrees, 30 min. east, and
27 degrees, 18 min. north as -18.5
and 27.3. Your computer then cal¬
culates bearings in true (not mag¬
netic) north and distance in land
(statute) miles, nautical miles and
kilometers .

When you get another reading,
you can keep or change your initial
start point (K/C). SAVE the pro¬
gram with GOTO 4000.

Beginners can learn from sub¬
routines earmarked with REMs in
this well prompted listing. For
example, GOTO 9977 to use a line
renumbering routine. (This routine
will not renumber GOTO and GOSUB
statements in the main listing;
you must change these yourself.)

DISTANCE serves as a subrou¬
tine in longer sea/air navigation
programs. I sell this and another
16K program for use with ham radios
that calculates distance/direction.
Each tape costs $5.

William Bosley, K3NN, 201 Highland
St. , Valparaiso, FL 32580

14

RHYTHM-FUN — 8K/1 6K

RHYTHM-FUN teaches basic rhythm
timing and sight reading for quart¬
er notes. Simply type in the pro¬
gram and RUN. You'll see four
measures of 4/4 time displayed,
with varied notes and rests. (Of
course, your computer makes no
sound.) Press ENTER to see more
randomly generated combinations.

Use RHYTHM with your students
or children. Instruct them to
count the beats displayed on screen
by clapping hands, tapping, whis¬
tling, or playing an instrument.

You can play different notes for
each bar to teach scales and rein¬
force note recognition.

Change line 950 PAUSE 4E4 so
displays change automatically. For
example, PAUSE 600 programs a dis¬
play change about every ten sec¬
onds, allowing hands-free program
use when playing an instrument.

In my experience as a music
educator, RHYTHM and other similar
programs dramatically increase
student participation and profi¬
ciency in exercises that previously
required memorization.

Individuals or software com¬
panies may contact me for sale of
my 12-Program Music Reading Library
(from quarter- to 16th-notes and
triplets) and six-program music
theory course.

John Dowlan, 8341 Boyce St.

Spring Hill, FL 33526

1 6

HIDDEN REMS

In PROGRAM ACCESS SECURITY
SYSTEM, location 16657 contains the
code 126. This code tells the
computer that the next five bytes
(in 16658-16662) are a numerical
constant. The display ignores the
six bytes, and does not print them
in the REM statement. Why?

When you enter a numerical
constant, say 999, the computer
stores this as the three bytes
representing 999, followed by code
126 and five bytes that represent
the floating point binary equiva¬
lent of 999. LIST never displays
the 126 or the following five
bytes, avoiding a screen full of
binary numbers.

Use this trick to hide infor¬
mation in your REM statements. To
hide a copyright message, for exam¬
ple, type in the following line.

Now POKE the locations of each X —
16517, 16523 and 16529— with code
126. Only the graphics remain.

PEEK these locations and you will
see the hidden message. Do this
anytime by preceding every five
characters with an X (which you
POKE to CHR$ 126). — RWK

17

CHEAP POWER

Surplus power supplies can
double a ZX/TS's load capabilities.

I use an Arizona Electronic Surplus
supply inside a big keyboard; no
more worries about power despite
the many peripherals I add to my
ZX/TS. Each unit costs $5.50 (2
for $10) and provides a regulated
5V, 2A output and 9-10V filtered,
but unregulated. Each comes with a
transformer and a 4" X 2.3" heat
sink. Except for the transformer,
all parts sit on a PC board. You
add the line cord and hook the unit
up to your ZX/TS. The unit comes
assembled, but uncased from Ari¬
zona Electronic Surplus, 12627 N.
Cave Creek Rd., Phoenix, AZ 85022,
602/971-0990.

How you connect this supply to
your ZX/TS depends on your system.

1) Use the transformer, bridge
rectifier and 2200 mF filter capac¬
itor outside your ZX/TS. This ups
the 9V current rating only.

2) Or build a really profes¬
sional circuit with a double pole
switch on the 5V and 9V lines.

Then you can use either the new
supply or your old wall pack. You
may want this since some devices,
such as Zebra's light pen, lie in
line with the wall pack (you cannot
use it any other way).

Paul Donnelly, Centerport, NY

At SYNTAX, we built option #2
using the following special parts
(in addition to the Arizona supply).
We used in-line connectors and fly-

ing

leads to connect

the power

— you

may

prefer a chassis-

-mounting

jack .

#

description

RS #

price

1

power cord

278-1255

S .79

1

3-conductor jack

274-274

.90

1

3-conductor plug

274-284

.85

1

metal utility box

270-253

4.79

1

DPDT switch

275-666

1.29

$8.62

We placed the transformer and
heat sink in a box as shown in the
diagram. Drill air inlet holes in
the box bottom, placed as shown by
circles. Make enough holes to
equal the vent area — 2.2 sq. in.

To get 9V, jumper the circuit
side of the board from the 9V pin

Space the circuit board from
the side of the box with 1/4 in.
thick insulating spacers. Bolt
the transformer to the bottom.
Mount the circuit board, regulator
up, near the box top to place the
heat sink near the top side vents.

Next solder the power supply
together as shown in the following
circuit diagram:

ZX/TS

REG.

PC BOARD

TRANSFORMER

9V

-°

-0 ^c>

4-*

5V 9V

TO COMPUTER
BOARD

Wire the 3-conductor plug and
jack so the tip carries 5V; the
middle, 9V and the sleeve, 0V.

To connect to your computer,
unsolder the 9V and 5V pins of the
ZX/TS regulator, bend them upward
and wire one end of the switch to
these pins. Next, wire and solder
the switch arms (center poles) to
the circuit where the regulator

18

pins were. Then solder the 5V and
9V from the jack for the Arizona
supply to the other switch end.
Solder the ground lead from the 3-
circuit connector to ground.

WARNINGS: 1) Never plug in

both supplies at the same time. 2)
Never interchange the 3— conductor
plug with the ZX/TS plug.

Another advantage to this set¬
up: the switch becomes an ON/OFF

switch. To cut the power off, just
switch to the other (unplugged)
power supply, then switch back to
the one in use. — RWK

MC INKEY$ SUBROUTINE — 8K/1K

Sometimes when writing a BASIC
program, you want to offer the user
a menu choice of actions. Several
methods let you input data, but of¬
ten programmers prefer the INKEY$
function. It does not require the
user to press ENTER after his or
her response. INKEY $ does have its
disadvantages — it's sometimes slow
to respond. Additionally, if you
program for novice users, you
should remember that pressing the
BREAK key causes your BASIC program
to stop. An inexperienced user may
not be able to start the program
again without destroying data (if
not the program itself).

This machine code routine re¬
turns the CODE value of the key
pressed to your BASIC program. You
can POKE it to ignore any entries
except for given low and high para¬
meters. This routine shows how to
use the ROM subroutines that scan
the keyboard and the routine that
decodes the scan.

Before calling this routine,
put the computer in SLOW mode as
the display disappears if RUN in
FAST. You can relocate the subrou¬
tine anywhere; it's usable in any
location because it contains all
relative jump instructions.

Start by entering the BASIC
program shown in Listing 1. Now,
hit RUN then ENTER without entering
a line number.

On the screen you'll see a
memory address and an L prompt. In
response to each prompt, carefully
enter the decimal numbers from the
following list, starting at the top
and working from the left along

each

205

row.

187

Hit

2

ENTER after each #
44 32 250 205

187

2

68

77

81 20

40

247

205

189

7

126 254

29

56

Now

you should

get

an out-of-

screen-memory report 5/130. Press
CONT then ENTER, and type these #s.
233 254 38 48 229 78 6

0 201

You now see report 9/210 at the
screen bottom. If you entered all
the numbers correctly, the # 3600
appears just under the listing.

Press LIST and ENTER to see
the listing again. The first line:

Now enter the demo program in
Listing 2 and press RUN 100 ENTER.

19

Try pressing keys 1-0 along the top
row, then other keys on the key¬
board. You see that the routine
works; the computer now accepts
only the choices displayed on the
screen as valid input.

To change the parameters, or
what input the computer will ac¬
cept, enter these lines with no
line number, substituting the prop¬
er values for low and high limit:

Decimal
Address

POKE 16534, CODE (low limit)

POKE 16538, CODE (high limit + one)
Remember to use the CODE and not
the number itself. See the back of
your ZX/TS manual for a complete
list of the character set codes.

Following is a commented list
of the machine language in this
subroutine .

Barry Boyer, West York, PA
Comments

Decimal Hex Mnemonic

START

16514

205

CDBB02

Call 02BBH j

•Call ROM scan keyboard

187

o

; routine.

16517

16518

44

2C

INC L

rCheck if user's finger
;on key.

32

20FA

JR NZ, START

;If so, go back and check

250

again .

AGAIN

16520

205

CDBB02

Call 02BBH

•Call ROM scan keybd.

187

2

16523

68

44

LD B,H

;Pass result of keybd

16524

77

4D

LD C,L

;scan in HL to BC.

16525

81

51

LD D,C

;Use D reg. to check for

16526

20

14

INC D

?no entry (no entry

?C=FFh) .

16527

40

28F7

JR Z, AGAIN

•If D=0 then C must have

247

•been FFh. Scan again.

16529

205

CDBD07

Call 07BDH

•Call ROM decode keybd

189

7

; routine.

16532

126

7E

LD A, (HL)

?HL now contains address

^pointing to keybd input,
;thus we load contents of

?this address into accum.

16533

254

FE1D

CP 1DH

^Compare to low parameter.

29

16535

56

38E9

JR C, START

rlf carry set, then input

233

;is below low parameter.

16537

254

FE26

CP 26H

?Else, check high

38

; parameter .

16539

48

30E5

JR NC, START

?If carry not set, then

16541

229

• input is above high
; parameter .

78

4E

LD C, (HL)

rElse, input OK. Load into
;C register.

16542

06

0600

LD B , 00

;Clear B register to 0 as

00

■the BC register is the
rvalue returned to BASIC
^calling routine.

16544

201

C9

RET

^Return to BASIC.

20

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EXCEPT
ZX PRO/FILE

BOOK REVIEW

Title:

Author :
Publisher :

Price :

ZX81/Timex

Programming in BASIC
&. Machine Language
Ekkehard Floegel
Elcomp
POB 1194

Pomona, CA 91769
$9.95, 139 pps .

Programming takes up where
your ZX/TS manual leaves off; the
book assumes you know the basics of
ZX/TS hardware and software.

Beginning chapters include
game, graphic, educational, and
data management programs. Eight
game programs and the "vehicle log
book program" nicely illustrate
some good programming techniques
(arrays and decimal point align¬
ment). The author provides good
programs that create basic graphics
motion, along with programs for
falling bodies, shooting objects,
plotting and vector effects of
gravity and horizontal velocity
(i.e. mortar shots). Unfortunate¬
ly, these contain many typographi¬
cal errors. Chapter four covers
school programs, including 12 math¬
ematical programs. Well written
data management programs clearly
show how to set up, maintain and
sort data files.

Unfortunately, Floegel gives
only a brief discussion of machine
language, in chapter six. This
chapter serves mostly those who
already have some idea of how to
use ML. A good, short ML monitor
program enhances the ML section.
About 30% of the book discusses
machine language.

Chapters seven and eight dis¬
cuss the Z80 PIO chip, and provide
a complete schematic for construc¬
tion of an inexpensive I/O board,
with software. Although the author
refers to a special set of proto¬
type boards, you could use almost
any ACE (all circuit evaluator, or
white board) to build the three-
chip I/O port.

Despite grammatical errors
such as choppy sentences, wrong
word order, and singular word forms
for plural (due to translation
from the original German) and style
(half-size, typed pages) the book
remains quite readable. Good BASIC
routines, the ML monitor program
and a simple I/O port proposal jus¬
tify this book's $9.95 price tag
(fixing the many typos would in¬
crease its value).

Paul Donnelly, Centerport, NY

CLASSIFIED ADS: Reach almost 9,000
ZX/TS users for only $9/line! We
must receive your typed copy (35
characters per line) with check or
money order by the 15th of any
month for publication in the fol¬
lowing month's issue. We print ad
exactly as you type it. We cannot
print fractions or cent symbols.
Please include your phone number if
not included in ad copy. SYNTAX,
Classified Ads, RD 2, Box 457, Har¬
vard, MA 01451.

Collector's editions of SYNTAX
QUARTERLY available from SYNTAX for
$9 an issue, 3/$25. (Winter 82,
Spring 83, Summer 83). Combine SQ
back issues and SYNTAX for money¬
saving combos: THE COMBINATION,
CATCH-UP and WORKS — see coupon on
p. 23 for details. Clip coupon or
call 617/456-3661 for fast service.
MC/VISA/AMEX/DINERS CLUB

16K/8K ROM++OUICKDRIVE++ZX81/TS1000
I lAccelerate your computer with 10
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screenf ill , INVERSE , more . Lis table ,
Explained. NO Mach, code exp. req.
ORDER NOW! SEND $12.95 to MICROLOAD
BOX 1095. TRUTH OR CONSEO..NM 87901

Ramdisk for $12.50? Its MICRODRIVE!
Use & store 8 FULL 2K progs AT ONCE
in 16K: fastsave, autoload, instant
access, all MC. BAFFLEBALL ! -Fastest
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PROG & CAT: SASE to RHEESWARE , 4001
Pennwood #3, Las Vegas, Nev. 89102

2 2

SYNTAX is published monthly by a wholly-
owned subsidiary of The Harvard Group.

Syntax ZX80, Inc.

RD 2, Box 457, Harvard, MA 01451. Telephone
617/456-3661.

12 issues, $29. Single issue, $4.

ZX PRO/FILE: the most advanced file
manager you can get for your Timex!
$16.95 for cassette and 59 pages of
tutorial explanations including a
programmers introduction to machine
code! Details are free : 603-586-7734
Tom Woods Box 64 Jefferson, NY 03583

Publisher:
Editor:
Assistant Editor:
Technical Consultant:

Kirtland H. Olson
Ann L. Zevnik
Lisa Fass Vivat
Richard Kelly

© Syntax ZX80, Inc., 1983. All rights reserved.
Photocopying prohibited. ISSN 0273-2696

OUR POLICY ON CONTRIBUTED MATERIAL

SYNTAX invites you to express opinions related to any Sinclair computer or
peripheral, or the newsletter. We will print, as space allows, letters discussing items
of general interest. Of course, we reserve the right to edit letters to a suitable length
and to refuse publication of any material.

We welcome program listings for all levels of expertise and written in either
Sinclair BASIC or Z80 machine code. Programs can be for any fun or useful
purpose. We will test run each one before publishing it, but we will not debug
programs; please send only workable listings. Programs submitted on cassette can be
tested more quickly and with less chance of error.

In return for your listing, we will pay you a token fee of $2.00 per program we
use. This payment gives us the nonexclusive right to use that program in any form,
world -wide. This means you can still use it, sell it, or give it away, and so can we.

We will consider submissions of news and hardware or software reviews. Please
keep articles short (350-400 words). Again, we reserve the right to edit accepted
articles to a suitable length. We will pay 7 cents per 6 characters, including spaces
and punctuation, for accepted articles.

When you send in programs for possible publication in SYNTAX, please
include the following information:

• How to operate the program, including what to input if it does not contain
prompts.

• Whether you can run the program over again and how.

• How to exit the program.

• The Syntactic Sum (program published in Feb. 81 and Jun. 81; send SASE
for a free copy).

• What RAM size program requires.

• What ROM program uses.

We pay for this explanatory text at the same rate as for articles in addition to
payment for the program itself.

If you want us to return your original program listing or article, please include
a self-addressed, stamped envelope. Otherwise, we cannot return submitted material.

*** EDGE CONN. ZX/TS, 23/46 WIREWRAP
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*****

$12 . 95 ( . 83
Box 813-2,

* Keep medical records

* of family members -

* Doctor Visits, Shots,

* Prescriptions, & more!

* 16K & 64K Versions.

NY tax) PYRAMID SOFTWARE
Pearl River NY 10965

WINKY BOARD II comp/caset INTERFACE
"worth its weight in gold": current
TIMEX SINCLAIR USER review w. photo
$14.95kit, $19.95built + $lP&H.Make
LOADing easy. Copy ANY ZX/TS cassett
+ more! G. RUSSELL, RD 1 Box 539,
Centre Hall PA 16828**814-364-1325*

CRASH PROOF AND PORTABLE POWER.

GET ZEE-PAC AND ADD YOUR OWN REG¬
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MAIN POWER FADES OR DIES. SHIPPED
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S983

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□ The Catch-up II (SYNTAX Jan. 82 -Jan. 84, SQ Winter 82-

Summer 83, plus 1 binder) . $77

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Summer 83, plus 2 binders) . $97

□ 12 issues of SYNTAX . $29

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These offers expire 30 Sept. 83 — SUBSCRIBE NOW

i

23

SYNTAX

** ADD MEMORY THAT WON'T FORGET 1 **
** New prices effective 9/1/83 **

** S & h included in all prices **

* Complete 2K kit . $34 :90 *

* 3 additional HM6116LP-3. $19:00 *

* Bare board with manual.. $15:00 *

* See RADIO-ELECTRONICS (Jul/Aug) *
**** ECONOMICAL EXPERIMENTING! ****
Keyed TS1000 44 pin connector $5:00
Piggy-back pc male connector $1:50
Shipping & handling per order $0:75
Instructions included - from HUNTER
*1630 Forest Hills Okemos MI 48864*

****** fast LOAD/SAVE PROGRAM *****

* *

* >>> Z-XLR8 ( Z-accelerate) <<< *

* *

* A Software Based Tape System for*

* 16K ZX81 & TS1000 . 6-10 X Faster*

* LOAD/SAVE. Create Program, Data,*

* Binary, & Graphics Files, Z-XLR8 *

* Takes ( 2K RAM & is Completely *

* Relocatable! No Hdwre Additions!*

* Cassette $11.00 ; EPROM $21.00 *

* ADVANCED INTERFACE DESIGNS *

* P.O. BOX 1350 *

* STATE COLLEGE, PA 16801 *

***********************************

****TEXTWRITER 1000/1500****

FULL TEXT EDITING-EASY TO USE. TAB,
BLOCK SAVE, AUTO. TEXT ALIGN, TIMEX
PRINTER. $11.95 TAPE - BOB FINGERLE
BOX 7793, FREMONT, CA 94537-7793.

********* MAZEBALL *********
All machine code. Seven screens.
This is a "bouncing ball" game that
makes the others look like toys!
***** TIMEBLASTERS *****
Over 3K of machine code makes this
the best of all the graphics space

wars - For serious arcade players!

***** METAGRAPHICS *****
At last! You can create elaborate
pictures using over 2000 different
graphics characters. BASIC and M/C.
All cassettes run on ZX81 or TS1000
/1500 ( 16K RAM). $12.95 (US) for 1
or $24.95 for all 3, postage paid.
Money back if you're not delighted.
******** CALLIOPE SOFTWARE ********
4130 Coe Dr. NE, Albuq. , NM 87110

EDUCATORS: Fall is here! Friendly,
comprehensive GRADEBOOK saves hours
Many features. TS1000 cass. $8.95
SVN , Box 2442, Hammond IN 46323.

****DATA MASTER-1 6-6 4K DATABASE****
FORMATTED PRINTOUTS, SEARCH/VIEW,
SEARCH/PRINT, EASY EDITING, INFORM,
13P MANUAL, AND MORE- $5 . 95-L . HARMON
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Tax Planner as pub. in SQ Summer 83
with improvements, '84 Tax Rates,
from author on cassette . $9 . 50 MO.
or check. Geschwind, 1714 Clarendon
Greensboro NC, 27410

nr

H\R\ARD

GRCXP

Bolton Road, Harvard, Mass. 01451

U.S. Postage
PAID

Harvard, MA
^ I *+ 0+ Permit No. 8

rirst Liqss 01451

MR WILLIAM TOMLINSON 58 68

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24